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Channel Estimation and Prediction Based Adaptive Wireless Communication Systems
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Wireless channels are typically much more noisy than wired links and subjected to fading due to multipath  propagation which result in ISI and hence high error rate. Adaptive modulation is a powerful technique to improve the tradeoff between spectral efficiency and Bit Error Rate (BER). In order to adjust the transmission rate, channel state information (CSI) is required at the transmitter side.

In this paper the performance enhancement of using linear prediction along with channel estimation to track the channel variations and adaptive modulation were examined. The simulation results shows that the channel estimation is sufficient for low Doppler frequency shifts (<30 Hz), while channel prediction is much more suited at high Doppler shifts with same SNR and target BER=10-4. It was shown that the performance at higher Doppler frequency shifts (<30Hz) was improved by more than 2dB over channel estimation at target BER=10-4 and 32QAM constellation used.

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Publication Date
Sun Apr 26 2020
Journal Name
Iraqi Journal Of Science
Extraction and Partial Purification of Exo-Polysaccharide from Lactobacillus Rhamnosus Isolated from Vaginal Specimens
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Lactobacillus spp. is one of the most important strains used worldwide in different applications that range from medical to industrial uses. Therefore, this study aimed to determine the potential capability of the putative probiotic L. rhamnosus isolated from clinical vaginal specimens to produce exopolysaccharide (EPS). From a total of 100 clinical samples, only 13 (13%) samples were represented as Lactobacillus spp, as characterized by the use of the API 50CHL system. The results revealed that the number of L. rhamnosus isolates constituted 4/13 (30.8%), with a confident percentage of more than 80%. In addition, characterization by 16S rRNA sequencing showed 100% similarity to the characterized species of L. rhamnosus. Also, the result

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Publication Date
Sun Apr 04 2010
Journal Name
Journal Of The Faculty Of Medicine Baghdad
Possible Association of HLA-DR and DQ Molecules with Autoimmune Hepatitis in Iraqi Patients
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Background: Human leukocyte antigen (HLA) is the most polymorphic genetic system in man. The genes of this region seem to influence susceptibility to certain diseases.
Patients and methods: Polymerase chain reaction-Sequence Specific Primers PCR-SSP is the method used to asses HLA-typing of 100 blood samples of 60 AIH patients and 40 healthy normal controls.
Results: An increased frequency of HLA-DR3, DR4 and DR7 was observed for patients group versus control group with P-value (0.0001, 0.05, and 0.001) respectively, while DR*0211 (DR2) may be formed the basis for protection against the disease. HLA-DQ on the other hand, yielded on association in Iraqi patients with AIH.
Conclusions: This finding de

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Publication Date
Thu Jun 08 2023
Journal Name
Iraqi Journal Of Laser
PDF The effect of nanoelectrodes number and length on enhancing the THz photomixer performance
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Abstract: Despite the distinct features of the continuous wave (CW) Terahertz (THz) emitter using photomixing technique, it suffers from the relatively low radiation output power. Therefore, one of effective ways to improve the photomixer emitter performance was using nanodimensions electrodes inside the optical active region of the device. Due to the nanodimension sizes and good electrical conductivity of silver nanowires (Ag-NWs), they have been exploited as THz emitter electrodes. The excited surface plasmon polariton waves (SPPs) on the surface of nanowire enhances the incident excitation signal. Therefore, the photomixer based Ag-NW compared to conventional one significantly exhibits higher THz output signal. In thi

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Publication Date
Mon Jan 28 2019
Journal Name
Journal Of The College Of Education For Women
Enlightenment of scientific knowledge at the kindergarten teachers and its relationship with some variables
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A kindergarten teacher is one of the most important elements in the educational process, since she is totally relied upon in kindergartens. Therefore, she could have basic and healthy characteristics to improve the educational process by directing the child towards a perfect growing upEducating and raising up a child should be an organized process that makes desirable changes in the child’s behavior in order to improve different sides of his personality, such as his appearance side, his mental side, and his social side.
This research aims at:
1- Measuring the scientific brilliance in kindergarten teachers.
2- Investigating the statistical significant differences of the scientific brilliance among kindergarten teachers in accor

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Publication Date
Sun May 12 2019
Journal Name
Journal Of The Faculty Of Medicine Baghdad
Attitude of Medical Students University of Baghdad toward Psychiatry:Clinical significance and as future career
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Background: Psychiatry is an important branch of medicine and has been an integral part of the academic curriculum in Baghdad College of Medicine since its establishment. Medical students have a different attitude towards it as a medical profession like other specialties of medicine and as future medical career.

Objectives: This study aims to explore the attitudes of medical students towards psychiatry in general and as a future career after their course of clerkship in the Department of Psychiatry in Baghdad Teaching Hospital.

Patients and Methods: During the year 2016, 158 male and female students of fifth and sixth years participated in a brief five-question survey der

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Publication Date
Tue Jun 16 2020
Journal Name
Journal Of The Faculty Of Medicine Baghdad
Epidemiology of the domestic and repatriation (Covid-19) Infection in Al Najaf province , Iraq
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ABSTRACT

Background: Al-Najaf province , Iraq , has experienced an outbreak of coronavirus disease 2019 (Covid-19). Epidemiological and clinical characteristics of (Covid-19) infection have been reported but a detailed clinical course and risk factors for mortality including medical comorbidities and severity of illness at time of presentation , have not been well described.

Methods: From February 24 to April 7, 2020, a case series study done on 123 PCR-confirmed cases of (Covid-19) admitted to Al-Hakeem Hospital And Quarantine Center (AHQC), in Al-Najaf Province, Iraq. Demographics, clinical and laboratory data  gathered from a local database at (AHQC). SPSS(statist

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Publication Date
Wed Feb 08 2023
Journal Name
Iraqi Journal Of Science
Morphological Description and Histological Structure of Adrenal Gland in Black Iraqi Partridge Francolinus francolinus
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The objective of this study was to investigate the morphological description and histological structure of adrenal gland in Iraqi black partridge Francolinus francolinus from Iraqi environment. Twenty adult healthy birds (male and female) were used in present study. They were measured and adrenal glands were removed, measured and fixed by 10% formalin and formalin and chromate fixative then stained with rotein histochemical stain (Harris hematoxylin and eosin stain (H&E), periodic acid Schiff (PAS), Azan and Mallory stain). The partridge had a small couple of adrenal glands of yellow colour they are located in abdominal cavity nearby the margin of superior kidney lobe. These are small, ovoid glands lying just cranial to the kidneys a

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Publication Date
Mon Dec 06 2021
Journal Name
Iraqi Journal Of Science
Detecting and Monitoring the Vegetal Cover of Karbala Province (Iraq) Using Change Detection Methods
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Karbala province was one of the most important areas in Iraq and considered an
economic resource of vegetation such as trees of fruits, sieve and other vegetation.
This research aimed to utilize change detection for investigating the current
vegetation cover at last three decay. The main objectives of this research are collect
a group of studied area (Karbala province) satellite images in sequence time for
the same area, these image captured by Landsat (TM 1995, ETM+ 2005 and
Landsat 8 OLI (Operational Land Imager) 2015. Preprocessing such as atmosphere
correction and rectification has been done. Mosaic model between the parts of
studied area was performing. Gap filling consider being very important step has
be

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Publication Date
Sat Oct 01 2022
Journal Name
Al–bahith Al–a'alami
HISTORY AND MODERNITY OF POETRY AS : A Reference Of The Modern Poem In Iraq
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One of the most important intellectual issues, which receive attention is the issue of modernity, it has occupied the scholars of all time. However, modern poetry used to have special care in Iraq and in the Arab countries .. it is not strange that the concept of modernity is linked to history .. or having history as the most important dimension of its dimensions .. because Arab poetry is historical and it is moving into an area of ​​the past that is still active in terms of language and literary image .. When some poets found that changing and modernizing poetry became a necessity of evolution, and one of the fundamentals of modernization, the cultural impact did not respond to the desire of poets, and their impulse in modern poetry

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Publication Date
Sun Sep 03 2017
Journal Name
Baghdad Science Journal
Measurement and purification of Alanine aminotransferase (ALT) enzyme activity in patients with celiac disease
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Celiac disease (CD) is the most common genetically - based disease in correlation with food intolerance. The aim of this study is to measure the activity of ALT enzyme and purify enzyme from sera women with celiac disease. Alanine aminotransferase (ALT) activity has been assayed in (30) women serum samples with celiac disease, age range between (20-40) year and (30) serum of healthy women as control group, age range between (22-38) year. In the present study, the mean value of ALT activity was significantly higher in patients with celiac disease than healthy group (p<0.01). The ALT enzyme was partial purified from sera women with celiac disease by dialysis, gel filtration using Sephadex G- 50 and ion exchange chr

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